To an outsider, particularly a non-Spanish-speaking outsider, corridos , with their oompah-oompah accordions and plaintive wails of yearning and loss, might seem like nothing more than sentimental ditties that look backward rather than forward. And they would be wrong. Despite their 200-year history and old-fashioned sensibility, corridos, or Mexican storytelling ballads, are all about the immediacy of the present, a bullet-riddled genre of music that has more in common with 50 Cent than with, say, Julio Iglesias. To paraphrase Public Enemy's Chuck D, today's corridos are the CNN of the barrio.

So asserts Mexican American filmmaker Natalia Almada in her debut feature-length documentary, "Al Otro Lado" ("To the Other Side"), which airs tonight as part of PBS's "P.O.V." series. In it, the filmmaker returns to her home town of Sinaloa, Mexico's drug capital, to explore immigration, trafficking and, of course, the music of a place that spawned corrido greats including Grammy-winning Los Tigres del Norte and the revered Chalino Sanchez, whose gangland-style slaying evokes comparisons to Tupac Shakur. Rather than make herself a part of the story, Almada instead chooses to tell it through the eyes of Magdiel, a 23-year-old fisherman, guitarist and corrido composer who contemplates sneaking to the other side -- the States -- in search of a better life: a home of his own, a nice new car and an education for his younger sister.

The result is an often affecting if sometimes meandering look at a topic that has so dominated the news of late. "Al Otro Lado" looks at all sides of the immigration issue with a dispassionate eye: There are the aging fishermen of Sinaloa struggling to cobble a living. The disaffected youths scheming ways to make it across the border. The "coyotes" who earn thousands of dollars escorting them across. The civilian Minuteman patrols that hunt them. The U.S. Border Patrol agents for whom finding dead migrants is a regular event. The Mexican American corrido singers struggling to maintain their culture and Los Tigres, who found fame and fortune in the States. All are given voice in "Al Otro Lado," cast against a swooning soundtrack of corridos.

Compelling stuff, to be sure. Still, it's tricky navigating so many disparate points of view; Almada packs a lot into the film's hour and all those voices clamoring for attention swamp the poignancy of Magdiel's story in the process. At times, it feels as if Almada is one of the fishermen that she portrays, trying mightily to hold onto a massive, wriggling fish. Still, for all its zigzagging across borders and story lines, "Al Otro Lado" somehow works.

This is in no small part thanks to the richness and complexity of the dilemmas facing would-be immigrants, embodied by the sweet-faced Magdiel. He's got a way with words and with the guitar. Shrimp fishing, a trade he learned from his father, only goes but so far. In Sinaloa, it is the drug dealers who rule.

Lured by the promise of an easier life, Magdiel thought about becoming a dealer or money launderer, he says, but the local thugs told him he'd be better off wielding a guitar. Write about us instead, they told him, and that's what he does, serving as the Cervantes of the barrio: A man tells him his story; Magdiel writes it down and sets it to music. For a price, of course. In 15 minutes he can come up with a song, a tale of gunslinging, drug-running and coyotes taking people across the border. His music is all about the here and the now, and the now is not so pretty. " Somos pobres ," he sings, " no puedo negarle " ("We are poor, I can't deny it.") For Magdiel, life in Sinaloa has become untenable, notwithstanding his songwriting sideline. He doesn't want to work in a factory for pennies a day, nor does he want to continue living with his parents, or become addicted to drugs out of sheer boredom. The world needs to hear his music, he says -- how will that happen if he stays in Sinaloa? What will he do once he's made it to the other side, where he imagines everyone is rich? He shrugs: Who knows?

"Al Otro Lado" ends on an open note, pondering the question rather than answering it. In this sense, too, "Al Otro Lado" is like a corrido, freeze-framing a moment in time.